Bach was in contact with Count Zeppelin and supported him in his plans to build a manoeuvrable airship. After initial scepticism ("Leave it be! You'll lose your money and your mind.") he eventually allowed himself to be persuaded ("You'll make it!"). Bach gave Zeppelin advice on materials and technology, wrote a positive expert opinion on the venture, and recommended him qualified graduates for his project. Bach became one of Zeppelin's most important advocates in the German Engineers' Association (VDI).